Electric drill.



F. W. KING. ELECTRIC DRILL. APPLICATION FILED DEO.15, 1909.

966,217, Patented Aug. 2, 1-910.

-L I V T v T 3 J /V T E 3' 7g UNITED STATES PATENT orr cu.

FREDERICK W. KING, OF CLEVELAND, OHIO.

anaemic DRILL.

Specification of Letters Patent.

Patented Aug. 2, 1910.

Application filed December 15, 1909. Serial No. 533,195.

T0 cllwhcmitmaa oncern:

Be it known that I, FREDERICK W. KING, 2. citizen of the United States, residing at Cleveland, in the county of Ouyahoga andv tors table orbench, and one that shall have its electric motor-counterbalanced and adapted to automatically close its own electric c1rcuit to operate the motor at the beginning of its movement, toward the work. These and other, features of the invention, which will be referred to later on, are illustrated, in

what is now considered a desirable form, by 5 1s a contact spring Q, which, when the motor the drawing in which:

Figure 1 is a. view partlyin elevation and j an opposlng spring R secured tov but insu lated from the base, as, shown at S in Fig. 3.

partlyin section. Fig. 2 is a side view of the lower portion of the same as seen from the direction of arrow 2 on Fi 1. Fig. 3 is a transverse section through t e base plate on the line 3.3 of Fig. 1. Fi 4 is a tra sverse section on the line 4-4= 0 Fig. 1 of't e guide fr me up n which the motor slides and a portion of the motor engaged thereby.

The mechanism is mounted upon and carried by a base plate A, preferably formed with depending side flanges a, and upon it is mounted a rotatable chucking device B adapted to hold lenses or similar fine work to be drilled. This chuck with its various slides and adjustments are not considered new with this invention as they are now to be found upon open market.

At one side of the base plate is secured a standard C provided at its upper end with channel guideways D, D in whlch is mount- ,ed a sliding head or block E to which is rigidly secured an electric motor F of any preferred construction adapted tothis position. The motor spindle or driving shaft G extends out of its lower'end and carries a chuck H in which may be secured a drill or other desired tool I. The motor and work chuck are in axial alinement and the motor adapted to move up and down in order to bring its tool into operation upon the work secured by the chuck.

Rigidly attached to the sliding motor head E is a vertical rod J provided with an adjusting collar K and passing through the top of the base plate A, as shown, with a spring L surrounding it between the collar and base plate. The office of this spring is to overbalance the weight of the motor, lift- .ing and holding it clear above and away I from the work in the chuck. On the lower end of this rod and inside of the base plate 'is secured a collar M which is acted upon by a leverN secured upon one end of a'rock shaft O mounted in suitable bearings in the 3 base plate and provided at its projecting extremity with a lever P by means of whlch the operator may draw down the motor and drill against the lifting stress of spring L.

On the outer side of the base and extending into the path of the operating lever P is a gage screw W which may be set to limit the throw of the lever as desired.

Secured-to the lower face of the collar is lowered, comes into spring contact with The electric circuit is diagrammatically shown in Fig. 1 where the line wire T extends from battery U to the motor wires at V; thence through the motor windings from which they are grounded on the metallic frame leading to and through the rod J to sprin Q, and thence, when in contact, to spring and by line T back to battery.

In the commercial operation of these drills sufficient electric energy may be derived from small dry cell batteries,-two of which are usually enough to give the required power although a greater number may be employed if deemed necessary.

In operation the piece of work to be operated upon is suitably placed in the chuck B and then by means of the lever P operating through shaft O, lever N and rod J, the motor is drawn down to the work, the elec tric circuit being closed at Q R at the first stage of this movement and the motor set into rotary action thereby. On the completion of the operation the lever P is released and the motor raised to its normal position of rest by the spring L, the circuit being broken on the separation of contacts Q B. By means of this arrangement electric current is used only when the drill is operating upon the work, thereby preventing any Waste battery power as might occur with ordinary switches that the operator might fail to open, either to save trouble between different operations or through forgetfulness.

The production of a drill press of this kind that may be operated with current produced by ordinary dry cell batteries is a commercially valuable invention. In large cities and at places where central power plants produce current for sale the power for running a drill of this character might be bought from such producer, but in small country villages and towns jewelers and others having use for such light drills may obtain dry cell batteries and be entirely independent of any power plants.

This device is shown as arranged particularly for drilling purposes but other than drilling tools might be held in the tool chuck on the motor spindle and perform other operations and this is considered to be within the province of the invention.

Having described my invention, I claim:

1. In a drilling machine, the combination of an electric motor adapted to operate a tool and be longitudinally movable on the line of its axis, an electric circuit including the motor, a switch in said circuit normally open when the motor is in normal. position most retracted from its work, with means whereby said switch is automatically closed upon the movement of said motor toward its work.

2. In a drilling machine, the combination of an electric motor adapted to operate a tool and be longitudinally movable on the line of its axis, means for retracting and yieldingly holding the motor away from its work, an electric circuit including the motor, a switch in said circuit normally open when the motor is in retracted position, with means for automatically closing said switch upon the movement of the motor toward its Work.

3. In a drilling machine, the combination of a base, a work chuck mounted thereon, a vertical guide post extending from the base, an electric motor movably mounted on said guide post and adapted to operate a tool, a spring adapted to retract and yieldingly hold the motor away from the work chuck,

with means for moving the motor against the pressure of said spring, an electric circuit including the motor, a switch in said circuit and a member actuated by the motormoving mechanism to contact with said switch and close the circuit and start the motor into rotation.

4. In a drilling machine, the combination of a base, a work chuck mounted thereon, a vertical guide post extending from the base, an electric motor movably mounted on said guide post and adapted through its spindle to operate a tool, a rod connectedto the motor and depending therefrom through the top of the base, an adjusting collar on said rod and a spring embracing the rod between said collar and the base with an electric circuit including said motor.

5. In a drilling machine, the combination of a hollow base, a vertical guide post extending from the base, an electric motor movably mounted on said guide post and adapted to operate a tool, a rod connected to the motor and depending therefrom through the top of the base, an adjusting collar on said rod and a spring embracing the rod between said collar and the base, a collar on the end of the rod inside of the base, a lever engaging said collar, a rock shaft mounted in bearings in the base and supporting said lever, with a hand lever mounted on said rock shaft outside of the base, and an electric circuit including the motor.

6. In a drilling machine, the combination of a hollow base, a vertical guide post ex-' tending from the base, an electric motor movably mounted on said guide post and adapted to drive a work tool, a rod con- .nected -to the motor and depending therefrom through the top'of the base, an adjusting collar on said rod and a spring embracing the rod between said collar and the base, a collar on the end of said rodand a contact on the rod, inside of the base, a lever engaging said collar, a rock shaft supporting said lever and mounted in bearings in the base, a hand lever on said shaft outside of the base, with an electric circuit including the motor and having a spring switch member having insulated support on the base with its free end lying in the path of the contact on said rod which is in ground circuit from the motor.

In testimony whereof, I hereunto affix my signature in the presence of two witnesses.

FREDERICK W. KING.

Witnesses:

H. R. SULLIVAN, E. L. THURSTON. 

